Verifying Answer to Wave Equation and Associated B Field

AI Thread Summary
The discussion revolves around verifying the derivation of the wave equation for the electric field E in empty space and the corresponding magnetic field B using Maxwell's equations. The initial derivation correctly leads to the wave equation, confirming that E = eyEycos(wt - kx) is a solution. However, there are concerns regarding the calculation of the curl of E and the subsequent integration to find B. Participants emphasize the need to correctly evaluate the curl, noting that it is a vector with multiple components. The conversation highlights the importance of accurate calculations in deriving associated fields from Maxwell's equations.
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Hi, I have the following question on my problem sheet, and I just want to check that my answer to it is correct as I need to use the result in a later problem. If someone could confirm it is correct, or point out mistakes/erros that would be great.

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Q. Derive the wave equation for E in empty space (Form the curl of Maxwell II and use a vector identity.). Find the condition that the plane wave E = eyEycos(wt - kx) is a solution (k=2pi/lamda). Use Maxwell II to find the B field associated with this electric field.
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A. I've done the derivation fine to get:

Laplacian E = epsilon-0.mu-0. d^2E/dt^2 [these are partial derivatives]

this is the same as d^2E/dx^2 = (1/c^2).(d^2E/dt^2) which can be solved using separation of variables to get E = eyEycos(wt - kx).

To find the associated B field, we used Maxwell II, ie. curlE = -dB/dt.

CurlE = -keyEysin(wt - kx)

B = integral - [curl E] dt

B = k/w. eyEycos(wt - kx)

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Thanks
 
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\vec{B}=-\int dt \nabla\times\vec{E}

What is the curl of \vec{E}...?And then evaluate the integral correctly.

Daniel.
 
dextercioby said:
\vec{B}=-\int dt \nabla\times\vec{E}

What is the curl of \vec{E}...?And then evaluate the integral correctly.

Daniel.

Isn't the curl of E in this case, just the value of E calculated earlier, integrated wrt x?
 
That curl is a vector and should have 2 components,namely on Ox_{1} and Ox_{3} axis of coordinates...

So it's incorrect what you have written.Please do the calculations again.

Daniel.
 
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